Pipe thrust machine for horizontal drilling

ABSTRACT

A pipe thrust machine for horizontal drilling operations, comprising a runway bed, a pipe thrust head, a driving structure supporting said head and slidable on said runways by interposition of bearing and supporting wheels, and hydraulic means for advancing said driving structure through the intermediary of expansible tenons engaging on seating provided on said runways, thus transmitting the reaction of the advancing thrust of the pipe to the runways in correspondence of the plane of the centre of gravity of the structure.

United States Patent 1 1 [111 3,881,558

Dolza May 6, 1975 [54] PIPE THRUST MACHINE FOR 3,174,562 3/1965 Stow 175/122 HQRIZONTAL DRILLING 3,232,360 2/1966 Dickinson... 175/122 X 3,347,521 10/1967 Bingham 6l/72.7 X Inventor: Claudw Della, 66 C0150 Francm, 3,587,755 6/1971 Slusher 175/122 x Turin, Italy 3,680,412 8/1972 Mayer 81/57.19 Filed: y 1973 3,726,506 4/1973 Vanderwaal 254/29 R [21] App]. No.: 364,297 Primary Examiner-Ernest R. Purser Assistant Examirzer-William F. Pate, III [30] Foreign Application Priority Data Attorney, Agent, or FzrmFlynn & Frlshauf June 9, 1972 Italy 68843/72 [57] ABSTRACT 52 us. Cl. 173/152; 61/72.7; 175/122; A P thrust machine for 1101110111111 drilling p 175/171; 254/29 R tions, comprising a runway bed, a pipe thrust head, a 51 1m. (:1. E21c 5/00 driving Structure Supporting Said head and Slidable 011 [58] Field of Search 173/152, 113; 175/171, Said runways y p tion of bearing and support- 175/122; 61/72.7; 8l/57.19; 254/121, 29 R ing wheels, and hydraulic means for advanclng sa1d driving structure through the intermediary of expansi- [56] References Cited ble tenons engaging on seating provided on said run- UNITED STATES PATENTS ways, thus transmitting the reaction of the advancing thrust of the pipe to the runways in correspondence of 2 aii' z s 1 the plane of the centre of gravity of the structure. 3:162:254 12/1964 Rose 175/171 15 Claims, 7 Drawing Figures PATENTEUMAY 6|975 QNN PSJENTED HAY 61975 SHEET 3 BF 3 PIPE THRUST MACHINE FOR HORIZONTAL DRILLING BACKGROUND TO THE DISCLOSURE The present invention relates to a pipe thrust machine for horizontal drilling operations, such as cutting through embankments or making road crossings or drilling of hill depressions, whereby lengths of pipes are juxtaposed in succession and welded together, a scroll auger acting therein for ejecting the removed material.

PRIOR ART Machines are known for carrying out horizontal drilling operations as aforesaid, but they are liable to inconveniences under heavy duty, especially in respect of maintenance of the horizontal drilling direction. Said inconveniences are due to the nature of the structure of the known machines, generally consisting of a bed placed on the ground in correspondence with the drilling zone and provided with a movable head for thrusting forward the lengths of pipe under the action of hydraulic means.

The dimensions of the bed are somewhat greater than those of the-head, especially in the longitudinal direction. In the case of asymmetrical forces of the pipe (for instance owing to compaction and/or hardness variations in the drilling ground), the machine unit is subjected to tilting couples and shows a tendency to deviate from the initial working position. Said phenomenon is particularly noticeable in respect with the tilting couple acting in the vertical plane of the machine, the thrust head being displaced in relation to the centre of gravity of the structure; accordingly, the thrust as applied to the pipe gives rise ,to a tilting couple not always balanced by the weight of the structure, thus limiting the maximum value of the drilling thrust.

A further inconvenience of the known machine consists in that the amplitude of the pipe-thrusting means is necessarily somewhat limited. In fact said thrusting means consists of hydraulic jacks which, for overall dimensions or axial stability reasons, must have a reduced stroke, for instance not longer than two metres, thus requiring the use of a large number of lengths of tubes during the drilling operations. This necessitates a frequent intervention of labour for installing and welding the successive length of tube, accordingly causing a substantial waste of time as well as poor overall efficiency of the machine. Moreover, the presence of numerous welds weakens the drilling pipe, thus limiting the bending stress of the same which can be accepted during the drilling excavation. A further inconvenience of the known machine is due to the simultaneous advancement of both the thrust head and the scroll auger, the latter being connected with the former. Accordingly, when meeting with rocky strata, and generally ground strata of greater compactness, it is not possible to precede the pipe with the auger except by adopting labour operations that can be carried out manually by gangs of men.

Additionally, the pipe when meeting with strata of greater compactness, not preceded by the auger and stressed by the thrust head, undergoes a deformation in correspondence with the end parts in contact with the above mentioned strata, said deformation invariably preventing the successive advancement of the pipe, thus frustrating the drilling operation.

OBJECT or THE INVENTION The main object of the present invention is to provide a machine for horizontal drilling as mentioned above, improved in such a way to obviate the described disadvantages of the known machines.

More particularly, an important object of the present invention is to provide a machine, the structure of which ensures drilling linearity, thus preventing any deviation and/or tilting couples due to off-centre reactions.

A further important object of the invention is to provide a machine capable of drilling operations with a limited number of lengths of tube, accordingly requiring a reduced number of welding operations, which on the one hand increases the structural stiffness of the drilling pipe, and on the other one makes the drilling operation more expeditious and economic.

A further object of the invention is to provide a machine provided with a pipe thrust head and a scroll auger connected therewith, the auger being movable in relation to the pipe, thus allowing the drilling operation to advance in the case of rocky strata or ground of difficult composition.

BRIEF SUMMARY OF THE INVENTION Accordingly, in order to carry out the above mentioned as well as further important objects as appearing from the following detailed specification, the invention provides a machine comprising a track bed, a pipe thrust head movable thereon'and supported by a driving structure slidable on said track bed by the interposition of bearing and guiding wheels; the driving struc ture being advancable by the action of hydraulic means acting, through expansible tenons on seatings provided on said track bed and transmitting to said seatings the reaction to the pipe advancing thrust, in correspondence with the plane containing the centre of gravity of said track bed.

FURTHER FEATURES OF THE INVENTION According to the invention, the seating for the expansible tenons of the driving structure are arranged along the tracks and spaced of a constant pitch, in such a manner that the advancing stroke of the pipe thrust head is a multiple of the expansion stroke of the hydraulic drive means. The latter have axial dimensions which can be contained within narrow limits, thus ensuring the rigidity of the whole structure, without it being necessary to use a large number of pipes of relatively short length. Due to the sliding tracks as above described for the driving structure, the advancement of the pipe can be of chosen extent. Furthermore, said tenons with cooperating seatings represent a bidirectional clamping permitting the extraction of both pipe and scroll auger, either after the drilling is over or, in the event of incidental damage, during the drilling operation.

A further important feature of the machine according to the invention resides in that the operating head of the scroll auger is axially fixed in relation to the driving structure and, on the contrary, in that the pipe thrust head is movable in relation to the structure, being supported at its end by stems that can be locked by radial check means. By said arrangement it is possible to impart relative movements between the thrust head and the auger, thus providing a drilling system suitable to various working requirements. More particularly by keeping the thrust head still, it is possible to set only the auger advancing when drilling through rocky strata or materials of a high compactness.

BRIEF DESCRIPTION OF DRAWINGS Further characteristics and advantages of the invention will appear from the following detailed specification, with reference to the accompanying drawings, given by way of non-limitative example, in which:

FIG. 1 is a side view of the improved machine according to the invention, showing the same in the operative drilling phase;

FIG. 2 is an elevation view showing the driving structure in detail;

FIG. 3 is a front view in direction of arrows III-III- of FIG. 2;

FIG. 4 is a view showing the pipe thrust head and its relative motion in relation to both movable structure and control auger head;

FIG. 5 is a section on line VV of FIG. 2;

FIG. 6 is a section on line VIVI of FIG. 3; and

FIG. 7 is a schematic section on line VII-VII of FIG. 4, showing radial check hydraulic means for the supporting stems for the pipe thrust head.

DESCRIPTION OF EMBODIMENT In the drawings, 10 designates in a general way the machine unit comprising a bed 11 and a driving structure 12 carrying the pipe thrust head. Said bed 11 is formed of two longitudinal members including angle section bars such as 11a, supported by vertical rods 13, rigidly fixed on a base plate 14. Said sectioned bars 11a, for instance of the C of double T type, delimit two runways l5 and 16 supporting the driving structure 12. Bearing wheels 18 react on to the runways 16 in order to absorb tilting couples arising in consequence of nonbarycentric strokes. The movable structure 12 carries the power assembly and supports, on its front part, a pipe thrust head 19. The latter is assembled in the space delimited by the two longitudinal members 11a, the axis of the head being contained within the plane of the centre of gravity of both movable structure and bed. Accordingly, the axis of the drilling pipe TR lies in the barycentric plane, so that the stroke performed by the head 19 in order to carry out penetration into the ground P, will also be barycentric. Said movable structure 12 is also provided with check means for transmitting the reaction of the stroke on to the bed 1 l, in such a manner that the resultant reaction is also barycentric in relation to the axis of said head 19. To this end the movable structure is provided with expansible tenons 20, arranged to engage corresponding notches or seatings 21 spaced along the sectioned bars of the bed, said seatings being spaced at a constant pitch. Said structure 12 is advanced along the runways 15, 16 of the bed by means of hydraulic jacks, a part of which for instance the cylinder, is integral with the movable structure, vwhilst the other part, for instance the piston rod, or vice versa, is integral with the tenons 20.

In order that the resultant of the drilling stroke reaction is barycentric as mentioned above, the dimension of the expansible tenons 20 is made equal to the height h of the sectioned bars. Said tenons 20 are slidably contained in a hollow frame 22, on which acts the rods 23,24,25,26 of the corresponding hydraulic cylinders,

coupled together as shown at 27,28. Said frame 22 con sists of two iron sections 22, 22b, appropriately spaced to contain said tenons 20, and comprising parallelepipeda having a high moment of inertia both in the longitudinal and in the traverse plane.

Each tenon 20,20a (FIG. 6) is also provided with a pivot 29,29a, each pivot protruding out of the section iron 22b of the frame 22 through a slit, respectively designated 30,30a.

The protruding part of said pivots is linked with the piston rod 31,32 respectively, of corresponding juxtaposd jacks 33,34 so that, when operated in expansion, they cause the ejection of said tenons 20,20a for engagement thereof with their respective seatings 21 and vice versa, as mentioned above, said jacks 33,34 having a double action. In order to feed the pipe during the drilling phase, said tenons are engaged into the corresponding reaction seatings 21 on the bed. Thereupon said jacks 27,28 are operated and the movable structure 12 moves along the runways 15,16; accordingly the head 19 drives the drilling pipe TR into the ground P, the reaction transmitting itself to the bed. Accordingly, the latter is anchored by providing it with an end slab 35 which is set in engagement by front contact with a purposely provided trench wall M. Furthermore, to ensure lateral stability, two end jacks 35a are provided which are expanded in order to effect engagement with the trench wall sides. The pipe advancement as achieved by the stroke produced by the head 19, occurs in concomitance with the action of a scroll auger contained in the pipe and set rotating by a driving head 36 supported by said structure 12 in a central position in relation to said head 19.

As soon as the above mentioned cylinders 27,28 have reached their maximum extension during the advancing stroke, the movable structure is in such a position that its reaction tenons 20 can engage into corresponding successive seatings 21a, 21b. Thereupon said tenons will be caused to re-enter the slit in the frame 22 and said jacks 27,28 will be retracted in order to bring the frame into correspondence with said successive seatings 21a, 21b; then, by operating said jacks 33, 34, the tenons will be expanded to engage the seatings, whilst the movable structure 12 will be pushed forward through the action of said jacks 27,28. In this way the total drilling stroke is equal to a multiple of the extension length of said bed 11. The head 19 consists of a plate 37 (FIG. 3) supporting four jaws 38, substantially crossing one another, for the engagement of the lengths of the tube TR; said plate 37 is centrally bored for the passage of the auger driving head 36.

According to the invention, said plate 37 is supported by the movable structure 12 by interposition of stems 41 (FIG. 4), so that said head is relatively shifted in relation to the movable structure 12, accordingly also in respect with the auger driving head 36. Said plate 37,

i and thus the pipe thrust head taken as a whole, can be relatively displaced in relation to the auger driving head 36. Radial driving means are provided, for instance hydraulically operated jaws 40 (FIG. 7), appropriate to clamp said stems 41 supporting the plate 37. Accordingly, the latter can assume several stationary positions as schematically shown in FIG. 4, in which the maximum separation position of the head is represented by dashes. If drilling is carried out while said. plate 37 of the head 19 is in an intermediate position or extracted in relation to the auger head 36, the latter can be set to feed forward with respect to the pipe TR, thus disengaging the stems 41 and permitting their reentry, whilst the movable structure 12 is urged forward by said cylinders 27,28. Accordingly, the drilling pipe TR is stationary, whilst the auger advances by boring rocky or compact ground strata, damage to the pipe in consequence of high stress being obviated.

It is worth noticing that the above mentioned advancing operation of the auger, and also the reverse movement, are carried out in an extremely simple and automatic way, by driving only the operating levers of the jaws 40 and of said jacks 27,28.

The machine unit as described above is hydraulically driven by a power plant including a convertor feeding pumps for the several hydraulic jacks and hydrostatic traction means for driving the auger head 36. It is a matter of course that, taking for granted the principles of the invention, the precise details of manner of carrying out the invention can be widely varied without departing from the scope of the invention as defined by the appended claims.

I claim:

1. A horizontal earth boring and pipe laying machine comprising:

a runway bed delimited by two space longituidnal members;

a movable carriage located in the space delimited by the two longitudinal members, the movable carriage having a vertical longitudinal barycentric plane midway between said longitudinal members and being adapted to carry a pipe;

bearing and supporting wheels on said carriage for mounting the carriage so that it is movable along the runway bed;

a pipe thrust head on said carriage for thrusting forward into the earth a pipe located in said barycentric plane;

hydraulic driving means coupled to said carriage for advancing said carriage;

tenons lockable against axial movement relative to said runway bed to provide an abutment for the hydraulic driving means, said tenons being positioned to transmit the resultant reaction of the advancing thrust of the pipe to the runway in said barycentric plane; and

a hollow frame for slideably containing said reaction tenons, the pistons of the corresponding hydraulic driving means acting thereonto.

2. A machine according to claim 1, wherein the length of the reaction tenons is equal to the height of said longitudinal members.

3. A machine according to claim 1, wherein said longitudinal members are made of metal sections and are provided with seats for the engagement of said reaction tenons, said seats being arranged along said longitudinal members and spaced at a constant pitch, the advancing thrust of said pipe thrust head being a multiple of the expansion stroke of the hudraulic driving means.

4. A machine according to claim 3, comprising opposed hydraulic jacks adapted to produce ejection of the tenons out of the hollow frame and their engagement with the corresponding seats on the runway bed.

5. A machine according to claim 1, wherein said longitudinal members are made of metal sections and are provided with seats for the engagement of said reaction tenons, said seats being arranged along said longitudinal members and spaced at a constant pitch, the advancing thrust of said pipe thrust head being a multiple of the expansion stroke of the hydraulic driving means.

6. A machine according to claim 5, wherein the length of the reaction tenons, as well as of the corresponding seats of said longitudinal members of said runway bed, is equal to the height of said longitudinal members.

7. A horizontal earth boring and pipe laying machine comprising:

a runway bed;

a movable carriage;

bearing and supporting wheels mounting said carriage movable along said runway bed, said carriage being adapted to carry a pipe;

a pipe thrust head mounted to said carriage for thrusting forward into the earth a pipe located in the common vertical longitudinal barycentric plane of said runway bed and carriage;

reaction tenons for transmitting the resultant reaction of the advancing thrust of the pipe to said runway in the same barycentric plane;

a hollow frame for slideably containing said reaction tenons, the pistons of the corresponding hydraulic driving means acting thereonto;

an earth working implement; and

a driving head for said working implement supported by the carriage and for operating said working implement through the interior of the pipe.

8. A machine according to claim 7, including stems for supporting said pipe thrust head at its ends; and radial clamping means coupled to said stems for locking said stems in position.

9. A machine according to claim 8, wherein said radial clamping means comprises hydraulically operated JaWS.

10. A machine according to claim 7, wherein said runway bed includes a pair of spaced longitudinal members, said pipe thrust head being located in the space delimited by said two longitudinal members of said runway bed; and the axis of the said pipe thrust head is contained in the barycentric plane of said runway bed and carriage.

11. A machine according to claim 10, wherein the length of the reaction tenons is equal to the height of said longitudinal members.

12. A machine according to claim 7, wherein said longitudinal members are made of metal sections and are provided with seats for the engagement of said reaction tenons, said seats being arranged along said longitudinal members and spaced at a constant pitch, the advancing thrust of said pipe thhrust head being a multiple of the expansion stroke of the hydraulic driving means.

13. A machine according to claim 12, comprising opposed hydraulic jacks adapted to produce ejection of the tenons out of the hollow frame and their engagement with the corresponding seats on the runway bed.

14. A machine according to claim 12, wherein the length of the reaction tenons, as well as of the corresponding seats of said longitudinal members of said runway bed, is equal to the height of said longitudinal members.

15. A machine according to claim 7 wherein said working implement comprises a scroll auger. 

1. A horizontal earth boring and pipe laying machine comprising: a runway bed delimited by two space longituidnal members; a movable carriage located in the space delimited by the two longitudinal members, the movable carriage having a vertical longituDinal barycentric plane midway between said longitudinal members and being adapted to carry a pipe; bearing and supporting wheels on said carriage for mounting the carriage so that it is movable along the runway bed; a pipe thrust head on said carriage for thrusting forward into the earth a pipe located in said barycentric plane; hydraulic driving means coupled to said carriage for advancing said carriage; tenons lockable against axial movement relative to said runway bed to provide an abutment for the hydraulic driving means, said tenons being positioned to transmit the resultant reaction of the advancing thrust of the pipe to the runway in said barycentric plane; and a hollow frame for slideably containing said reaction tenons, the pistons of the corresponding hydraulic driving means acting thereonto.
 2. A machine according to claim 1, wherein the length of the reaction tenons is equal to the height of said longitudinal members.
 3. A machine according to claim 1, wherein said longitudinal members are made of metal sections and are provided with seats for the engagement of said reaction tenons, said seats being arranged along said longitudinal members and spaced at a constant pitch, the advancing thrust of said pipe thrust head being a multiple of the expansion stroke of the hudraulic driving means.
 4. A machine according to claim 3, comprising opposed hydraulic jacks adapted to produce ejection of the tenons out of the hollow frame and their engagement with the corresponding seats on the runway bed.
 5. A machine according to claim 1, wherein said longitudinal members are made of metal sections and are provided with seats for the engagement of said reaction tenons, said seats being arranged along said longitudinal members and spaced at a constant pitch, the advancing thrust of said pipe thrust head being a multiple of the expansion stroke of the hydraulic driving means.
 6. A machine according to claim 5, wherein the length of the reaction tenons, as well as of the corresponding seats of said longitudinal members of said runway bed, is equal to the height of said longitudinal members.
 7. A horizontal earth boring and pipe laying machine comprising: a runway bed; a movable carriage; bearing and supporting wheels mounting said carriage movable along said runway bed, said carriage being adapted to carry a pipe; a pipe thrust head mounted to said carriage for thrusting forward into the earth a pipe located in the common vertical longitudinal barycentric plane of said runway bed and carriage; reaction tenons for transmitting the resultant reaction of the advancing thrust of the pipe to said runway in the same barycentric plane; a hollow frame for slideably containing said reaction tenons, the pistons of the corresponding hydraulic driving means acting thereonto; an earth working implement; and a driving head for said working implement supported by the carriage and for operating said working implement through the interior of the pipe.
 8. A machine according to claim 7, including stems for supporting said pipe thrust head at its ends; and radial clamping means coupled to said stems for locking said stems in position.
 9. A machine according to claim 8, wherein said radial clamping means comprises hydraulically operated jaws.
 10. A machine according to claim 7, wherein said runway bed includes a pair of spaced longitudinal members, said pipe thrust head being located in the space delimited by said two longitudinal members of said runway bed; and the axis of the said pipe thrust head is contained in the barycentric plane of said runway bed and carriage.
 11. A machine according to claim 10, wherein the length of the reaction tenons is equal to the height of said longitudinal members.
 12. A machine according to claim 7, wherein said longitudinal members are made of metal sections and are provided with seats for the engagement of said reaction tenons, said seats being arranged along said lonGitudinal members and spaced at a constant pitch, the advancing thrust of said pipe thhrust head being a multiple of the expansion stroke of the hydraulic driving means.
 13. A machine according to claim 12, comprising opposed hydraulic jacks adapted to produce ejection of the tenons out of the hollow frame and their engagement with the corresponding seats on the runway bed.
 14. A machine according to claim 12, wherein the length of the reaction tenons, as well as of the corresponding seats of said longitudinal members of said runway bed, is equal to the height of said longitudinal members.
 15. A machine according to claim 7 wherein said working implement comprises a scroll auger. 